Shaving

[veganrob]

A few years ago I was in the chiropractor office. Was summer, wearing shorts. A younger, attractive woman was there and saw DC before me. When I went back later he told me the woman asked about my legs. He explained that I was a serious biker. She said" Oh I hate it when a guy has nicer legs than I do"

Keep your legs shaved and sexy

 

[Boeing]

there are other benefits.

how often do you shave?

Surfing it is easier to get the wetsuit on and off. Less inner thigh chaffing sitting on the deck when the water warms and we are board shorts only.

I have to keep them clean daily because I wear slacks for business and stubble on the thigh can kill a good pair of slacks in just days

then there is sleeping with stubble. it can kill the sheets or kill the deal etc...

 

[ImmaculateKadence]

Really? Sorry, don't believe it. Ever see a golf ball? Why's the surface dimpled?

I thought it had more to do with creating backspin that lifted and carried the ball farther, not so much as decreasing aerodynamic drag, though it does do that as well.

Ok for the million and 1st time in response to this much quoted trial:
- mountain bike racers shave their legs, what are their average speeds?
- ever seen a skin suit and aero everything else? The amount of exposed hair on today's cyclists is minimal. If it matters so much, why are many cyclists not shaving their faces?
- was the 0.6% for somone who had 80 hairs per cm2 or 800?
- several other studies since then have been unable to show any significant advantage of shaved legs.

I actually started shaving as a mountain biker. It had more to do with rubbing trees and bushes than reducing drag, but once I started my legs felt cooler and better. Haven't stopped since, and it feels even better on the road.

I think the drag reduction will vary with the amount of hair. If a dude has legs like sasquatch, it will save much more than some dude with a little fuzz.

 

[oncehadhair]

Strangely quiet today.

Which clearly you haven't. You lack all credibility.

And while you trying to find all the pieces of your shattered credibility you might like to apologise. That's two you owe me now.

I'm not optimistic - you have no class.

 

[oncehadhair]

Oh really? Chester Kyle 1987 says it's worth 5 seconds over 40km at 37km/h. That sounds like a measurement to me.

You believe he is wrong? Back up your claims with something other than empty headed opinions.

Claims backed up.

If Kyle's findings had any real scientific impact they would have been published in a scientific journal, not Bicyling magazine.

Apology accepted.

 

[JeffreyPerry]

I can remember when I first shaved my legs... the wife was appalled I was even considering such an "un-manly" thing. Well, the next day she was like..."they actually are very nice this way. Don't stop." Been shaving ever since.
As for the aerodynamic advantages, I don't really care about studies...Bike company spends hundreds of thousands of dollars to develop aerodynamic downtubes. Obviously, if the minute difference between a round tube and a elongated teardrop shaped tube will increase the aerodynamic performance....so will me shaving my sasquatch legs.

 

[Polyarmour]

Oncehadhair.

Thanks for the reference. Let me say I think you were a bit premature with your demands for an apology.

I think you have completely misunderstood the paper you have referenced so I will explain it to you.

In simple terms what the paper is trying to do is to come up with a computer calculation method for drag that correlates with what is measured in the wind tunnel. So if the computer method is accurate enough... there would be no need to do anymore wind tunnel testing. Please note that the computer calculation methods only got to within 7-11% of measured figures. I think we are all agreed that the forces involved with leg shaving are much less than these margins of error.

Also note that the paper states that shaving the legs will decrease drag. Yes you've quoted a paper that contradicts your main point! Unbelievable but true.

Viscous drag
can be reduced by lowering the surface roughness, for example by wearing a smooth suit or by shaving the skin.

Firstly,
"...Wall functions are used to model the boundary layer, except by
Barber et al. (2009). Wall functions can however result in inaccurate predictions of wall friction and boundary layer transition from a laminar to a turbulent boundary layer (Casey and Wintergerste, 2000)..."

Yes wall functions are inaccurate, ie the calculation method used didn't replicate reality very well. This has nothing to do with drag from leg hair. The fact that you used this as evidence to support your assertion illustrates that you didn't understand the article.

And, further,
"...the predicted skin-friction drag should be lower in the CFD simulations.
Since it is only a small percentage of the total drag for bluff bodies, namely about 5% in this study (predicted by CFD simulations), the resulting decrease of the total drag will be limited and could even not be noticed..."
In other words the effect of skin friction, on the whole body is lost due to the effect of other, more significant variables.

Once again this refers to the lack of correlation between the calculation method and what is measured in practice in the wind tunnel. Once again nothing to do with shaved legs. Once again you don't know what you're talking about.

Also:
"...More important however is the fact that surface roughness could alter the locations where boundary-layer separation occurs on the cyclist’s surface by which the flow field around the cyclist will change and therefore also the resulting form drag. Under appropriate conditions, a boundary layer could remain more attached on a rough surface (i.e. in the wind tunnel in this study) by which the wake zone and therefore also the total drag are reduced (Wilson, 2004). This could explain why the “smooth” cyclist of CFD exhibits a systematically higher drag area..."
Which completely refutes your claims.

Aah, not so fast sunshine. You see, you might think quoting out of context mumbo jumbo is going to fool everyone but this happens to be an area I work in. I would say stick to your statistics. The paragraph you have quoted is within a section discussing how well the calculations match reality with the author attempting to explain the differences. Once again nothing to do with shaved legs making you go faster.

Mate is this the best you've got?

That was downright embarrassing.

As was this:

Claims backed up.

If Kyle's findings had any real scientific impact they would have been published in a scientific journal, not Bicyling magazine.

Apology accepted.

 

[Boeing]

all right since we are back on topic, anyone shave just a little higher than the thigh? come on guys its all good.

 

[The Barb]

Check out the photo of Hincapie's leg at this link (you need to scroll down a bit):

http://everettstilley.blogspot.com/2011/07/tour-de-france-stage-5-return-of-man.html

How the hell does he shave that?!?!

 

[rata de sentina]

Read my original post sockpuppet, the bit where I cited

Hang on a minute there, now I feel obliged to hop in here because although you may be correct is that a peer reviewed journal you are citing?

 

[veganrob]

all right since we are back on topic, anyone shave just a little higher than the thigh? come on guys its all good.

Hahah. i'll be the first. GF requests it be trimmed up a bit so I oblige.
All shaved down just does not look right.

 

[Boeing]

Check out the photo of Hincapie's leg at this link (you need to scroll down a bit):

http://everettstilley.blogspot.com/2011/07/tour-de-france-stage-5-return-of-man.html

How the hell does he shave that?!?!

wow my grandmas legs dont even look like that. is that healthy?

 

[ImmaculateKadence]

wow my grandmas legs dont even look like that. is that healthy?

It's just varicose veins, and the condition is largely genetic. Cycling or other strenous activity has no effect on it. Basically, the blood is no longer flowing properly in those veins. They can be painful and itchy, but not totally unhealthy.

When I first saw a pic of Hincapie's legs, I was so worried that cycling would cause me to develop varicose veins. My primary care physician told me not to worry, unless members have my family have them.

 

[oncehadhair]

That was downright embarrassing.

Very astute of you to sort out the point of the article, and after so little time. Well done.

And its only fair to hold back on the apology if there is something you don’t quite get, so let me help you a little.

Quite correctly you state that the aim was to compare a model with a rider in a wind tunnel. The experiment wasn't just about shaved legs. But you shouldn’t throw the baby out with the bath water. Results were obtained from the model and from the cyclist. It doesn’t make its findings about drag less valid. But the findings are stated in the results – which is where my quotes came from .

In your attempted rebuttal you seemed confused. Confused about the difference between a scientific journal and a magazine and confused about an assumption made when carring out an experiment and the results of an experiment.

In an effort to discredit me you quoted from the introduction in an effort to make a point. Yes, you quoted an assumption that was made in the introduction, not a result of the experiment, not a finding of the study! Unbelieveable but true.

Let me lead you through your error: In the introduction they made the assumption that shaving would be a contributor to a reduction in visous drag. Thought that might catch your eye. But you, conveniently or ignorantly, didn't see that the results of the experiment, comparing the expectations for surface drag of the smooth model with the rough cyclist in a wind tunnel, didn’t support that. In fact quite the opposite, the results showed that the drag of a smooth body is greater than that of a rough one. So much for hairless legs. So much for your attempted rebuttal.

Unless you can support your claim that shaving makes a difference with a scientific study you have no argument. And so far you have no argument because the “study” you (and many others) quote was neither peer reviewed nor published in a scientic journal. Anyone, even you, can get published in a magazine. And Kyle’s “study” was specificially carried out for the magazine. They paid him to do it. Conflict of interest already! No one checks the method or reviews the results for a magazine article.

So your claims have no foundation. And mine do.

And embarrassed? Only for you, mate. Now about that apology.

 

[Granville57]

Not that I'm interested in reigniting the debate of the previous pages, but Michael Barry's take on the topic is worth a look.

Razor's Edge: Shaving Your Legs for Cycling

http://www.bicycling.com/training-nutrition/training-fitness/razors-edge-shaving-your-legs-cycling

No one knows which cyclist first shaved his legs, or why. In his blog, the frame builder and amateur cycling historian Dave Moulton writes that racers have done so for at least 100 years and surmises that the practice likely predates the adoption of the custom by Western women (which is commonly believed to have begun in the early 1900s, with the popularization of short hemlines and more-revealing swimsuits). The authenticity of the often-cited motivations--cleanliness, style, facilitating massage, aerodynamics, and ease of treating road rash--is similarly murky.

 

[Paco_P]

OK, for the billionth time ...

A 1987 study conducted by Chester Kyle concluded that the aerodynamic improvement of shaving legs is roughly 0.6 percent, which could result in a savings of around 5 seconds in a 40km time trial ridden at 37kph. (Kyle, Chester R.; Zahradnik, Fred: Aerodynamic Overhaul. Streamline Your Body and Your Bike. Bicycling, Jun 1987, pp. 72 - 79)

That, my little friend, is a significant margin in a time-trial, even more so at today's 45kph+ speed.

What was the statistical significance of the claim? When you phrase it as a savings of 5 seconds over 40km, I doubt very much it has any significance. That is to say it seems to me the claimed results show that it makes no difference how hairy the cyclist is.

 

[oncehadhair]

What was the statistical significance of the claim? When you phrase it as a savings of 5 seconds over 40km, I doubt very much it has any significance. That is to say it seems to me the claimed results show that it makes no difference how hairy the cyclist is.

The "study" referred to was commissioned by bicycling magazine and has been quoted as a benchmark by cyclists and triathletes for years. It has not been published in any recognised journal.

You pay me to tell you how much time you will save if you shave your legs and I'll come up with a figure, no worries.

As you observed, it is not possible that such a small figure can have any statisical significance. I'm sure the likes of the poster you quoted count the tenths of a second with each razor stroke up their leg.

 

[Magnus]

As you observed, it is not possible that such a small figure can have any statisical significance. I'm sure the likes of the poster you quoted count the tenths of a second with each razor stroke up their leg.

Any figure, however small it is, can have statistical significance, even if it has no, in reality, meaningful significance.

 

[Polyarmour]

Ok Oncehadabrain I'll try one more time but I suspect you are beyond help.

Let me lead you through your error: In the introduction they made the assumption that shaving would be a contributor to a reduction in visous drag. Thought that might catch your eye. But you, conveniently or ignorantly, didn't see that the results of the experiment, comparing the expectations for surface drag of the smooth model with the rough cyclist in a wind tunnel, didn’t support that. In fact quite the opposite, the results showed that the drag of a smooth body is greater than that of a rough one. So much for hairless legs. So much for your attempted rebuttal.

1/. It was NOT an assumption. Where did it say it was an assumption? You made that up! It was presented as FACT. Because it is FACT that smooth bodies have a lower coefficient of drag. This is not arguable. Shaved legs are smoother than hairy legs, shaved legs have less drag, shaved legs therefore go faster, this is FACT. If you knew anything about fluid mechanics you would understand this. If you don't believe it, start wearing knitted alpaca tights in your races and tell us how you go.

2/. The paper did NOT show that a smooth body had less drag than a rough one. You don't understand what you are reading. The author invented a computer model. The computer model was a bit limited in replicating what happens in a wind tunnel. The author then trys to explain what would have caused the differences. This is what the paper was about.

3/. This was NOT even an article about shaved legs. You initially said there were studies that showed there was no significant advantage of shaved legs. I asked you to tell us the about the studies. You came back with a study that wasn't even about shaved legs. There was ZERO discussion in this entire article about the affect of shaving legs, other than the FACT stated in the introduction that shaving the legs reduces drag.

Unless you can support your claim that shaving makes a difference with a scientific study you have no argument. And so far you have no argument because the “study” you (and many others) quote was neither peer reviewed nor published in a scientic journal. Anyone, even you, can get published in a magazine. And Kyle’s “study” was specificially carried out for the magazine. They paid him to do it. Conflict of interest already! No one checks the method or reviews the results for a magazine article.

So your claims have no foundation. And mine do.

And embarrassed? Only for you, mate. Now about that apology.

1/. You haven't even read Chester Kyle's study and you have no idea what research it was based on.

2/. The fact that a researcher presents a summary of his research for a magazine does not warrant dismissal of his findings. Once again, get a copy of his paper and tell us where he is wrong rather than trying to muddy the waters with your bull$h17.

 

[usedtobefast]

lets look at it from another way. a tornado blows all the leaves off a tree. the leaves have a lot of drag,eh? so they are sitting ducks for the big wind. once they are gone the tree has a better chance of surviving the storm.
hairy legs catch air. they do. shaved legs let the air flow around. it is pretty simple.

 

[Polyarmour]

Wear a Castelli Aero Jersey and you get 10W.
That's a jersey that looks the same as other jerseys.
Yet it's worth a minute over 40km.
Not hard to imagine hairy legs slowing you down 5 seconds over the same distance.

 

[oncehadhair]

1/. It was NOT an assumption. Where did it say it was an assumption?

Um, der, because it was in the INTRODUCTION, it was not a finding. They specifically say they couldn't study viscous drag because even the 5% estimate for the whole body was impossible to isolate from other signifcant drag as a result of rider position.

The paper did NOT show that a smooth body had less drag than a rough one.

Well, it did. It was one of the reasons that the results of the model didn't align as well as they could have with the actual rider.

3/. This was NOT even an article about shaved legs.

Yes, you have me there. I remember reading such an article in the mid 90's but have been unable to find it - I realise that sounds convenient there's not much I can do about it. I would suggest the reason why there has been no further studies is because it is impossible to isolate the effect of shaved legs from other more significant variables.

But the results showed that a smooth body has more drag than a rough one.

The effect of visous drag (in the article I quoted) for the whole body was estimated to account for 5% or less of total drag of a cyclist - and wasn't studied because even 5% is lost among other variables like rider position. So how can Kyle isolate 0.6% of total drag for shaved legs?! Or achieve a 12% improvement in viscous drag from shaving the hair from maybe 10% of the surface of the body. LOL to coin a well used phrase.

2/. The fact that a researcher presents a summary of his research for a magazine does not warrant dismissal of his findings. Once again, get a copy of his paper and tell us where he is wrong rather than trying to muddy the waters with your bull$h17.

Sorry buddy, this was no summary, read the words FROM THE MAGAZINE ITSELF "a 1987 study conducted by Chester Kyle for this magazine"
(http://www.bicycling.com/training-nutrition/training-fitness/why-do-cyclists-shave-their-legs).

Not a summary. The whole kit and caboodle. Not an abstract. And certainly not a scientific study.

A bit of educated number crunching to entertain readers with the level of scientific understanding displayed by the likes of you. An educated guess for cyclists who want to think that leg shaving will make a difference. And I assume he didn't do it for nothing.

And you are right, I haven't read the article, but I am able to spot a number that is not right from a long way off. I have looked everywhere for a copy and would be happy to review it for you if you can send me a one, but I suspect you haven't read it either.

And its good to see you had a little fun with my forum name, I'm sure it took you hours to come up with that one.